Ammonia type diazo machines for the preparation of copies of translucent originals are well known in the art. In general, such machines are provided with a printer section where a high intensity light exposes sensitized material through an original document to be copied. A separator section then separates the original from the sensitized material and transports the sensitized material to a developer system. In the developer system, the exposed sensitized material is processed or developed by exposure to vapor of a volatile developing agent or ammonia gas. The developed copy is then transported from the developer section and provides a high quality permanent copy of the original document.
To supply the developer system with ammonia fumes for developing the copy, it is conventional practice to pump the ammonia from a shipping container to the developing system. In some instances, the unused ammonia is recirculated to the container to avoid escape of ammonia fumes to the atmosphere. One such arrangement is shown in U.S. Pat. No. 3,535,997. As shown therein, the device comprises a developer tray, a container of ammonia developer, a pump and two ducts. The first duct conveys the ammonia from the container to the tray and the pump circulates the ammonia vapor into the tray and, via the second duct, to the container.
While such an arrangement might reduce escape of ammonia fumes to the atmosphere during operation of the machine, it does not provide for preventing escape of ammonia fumes from the container during the interchange of an empty container with a container providing a fresh supply of ammonia. Hence, and as shown in the reference patent, in the course of interchanging the containers it is necessary to remove a plug from the empty container, remove a cap from the full container and to substitute the plug for the cap of the container providing the fresh supply of ammonia. In so doing, of course, the ammonia fumes and vapor from both the empty container and the full container are discharged to the ambient atmosphere until such time as the empty container is capped and the full container is provided with the plug for blocking the neck of the container. Because the device does not prevent the escape of ammonia fumes during the interchange of the containers, the room in which the machine is installed becomes fouled with objectionable ammonia odor.